Windows Shares cannot be seen??

I have my MBP and a windows machine hooked up through a router. I have shared folder on the PC which I access with my MBP. It's been this way for about 6 months, now when I click on "Network" it doesnt do anything at all and I cannot view anything. My windows PC hasnt changed at all, in fact, every machine on the network (All other PC's) can see eachother and share files without any issues. However my mac for some reason cannot see anything now. Anyone know what might be the problem with my MBP?

More than likely, your windows machine obtained a new IP address via DHCP (providing you're using that) from the router and the Mac is looking for the old address. Try doing: ipconfig from a DOS command line on the PC and write down the IP address. Then map to the PC via IP address- it'll likely go through. I do that this way: